Intraoperative cone-beam CT spatial priors for diffuse optical fluorescence tomography.

Intraoperative cone-beam CT spatial priors for diffuse optical fluorescence tomography. Phys Med Biol. 2019 Sep 30;: Authors: Daly MJ, Chan H, Muhanna N, Akens MK, Wilson BC, Irish JC, Jaffray DA Abstract A hybrid system for intraoperative cone-beam CT (CBCT) imaging and continuous-wave fluorescence tomography (FT) has been developed using an image-guidance framework. Intraoperative CBCT images with sub-millimeter spatial resolution are acquired with a flat-panel C-Arm. Tetrahedral meshes are generated from CBCT for finite element method implementation of diffuse optical tomography (NIRFAST). Structural data from CBCT is incorporated directly into the optical reconstruction process using Laplacian-type regularization ("soft spatial priors"). Experiments were performed using an in-house optical system designed for indocyanine green (ICG) fluorescence. A dynamic non-contact geometry was achieved using a stereoscopic optical tracker for real-time localization of a laser diode and CCD camera. Source and detector positions were projected onto the boundary elements of the tissue mesh using algorithms for ray-triangle intersection and camera lens calibration. Simulation studies showed the capabilities of a soft-prior approach, even in the presence of segmentation uncertainties. Experiments with ICG targets embedded in liquid phantoms determined the improvements in the quantification of the fluorophore yield, with errors of 85% and <20% f...
Source: Physics in Medicine and Biology - Category: Physics Authors: Tags: Phys Med Biol Source Type: research